1. Field of the Invention
This invention relates generally to methods and structures for implementing software redundant array of inexpensive disks (RAID) logic and more particularly using a central processing unit (CPU) and input/output (IO) devices of a host to implement software based RAID.
2. Description of the Related Art
A computer system typically requires large amounts of secondary storage, such as a disk drive, to store information (e.g. data and/or application programs). Redundant arrays of inexpensive disks (RAID) subsystems are commonly employed to address the large storage requirements. In addition, RAID subsystems provide a high degree of reliability because of their redundant nature.
RAID storage systems can be implemented in hardware or software. In the hardware implementation the RAID algorithms are built into a controller card that connects to the computer input/output (IO) bus. However, including a full-RAID intelligent controller adds significant cost to the RAID subsystem. In, the software implementation of RAID, commonly referred to as host based RAID, the RAID algorithms are incorporated into software that runs on the main processor in conjunction with the operating system. In software based RAID, the operating system, such as WINDOWS NT™ or NOVELL NETWARE™, running on the host CPU, handles all the array control functions. Accordingly, software based RAID is a low cost RAID implementation with no added expense for array control hardware. However, current add-on implementations of host based RAID require the user to purchase RAID specific IO channels in order to plug into the motherboard.
As a result, there is a need to solve the problems of the prior art to provide host based RAID that is able to take over any channels or IO devices on the motherboard without the need to purchase RAID specific IO channels.